os.chdir() is the Pythonic version of cd.
The Path objects in path library offer both a context manager and a chdir method for this purpose:
from path import Path
with Path("somewhere"):
...
Path("somewhere").chdir()
import os
abs_path = 'C://a/b/c'
rel_path = './folder'
os.chdir(abs_path)
os.chdir(rel_path)
You can use both with os.chdir(abs_path) or os.chdir(rel_path), there's no need to call os.getcwd() to use a relative path.
os.chdir() is the right way.
If you're using a relatively new version of Python, you can also use a context manager, such as this one:
from __future__ import with_statement
from grizzled.os import working_directory
with working_directory(path_to_directory):
# code in here occurs within the directory
# code here is in the original directory
UPDATE
If you prefer to roll your own:
import os
from contextlib import contextmanager
@contextmanager
def working_directory(directory):
owd = os.getcwd()
try:
os.chdir(directory)
yield directory
finally:
os.chdir(owd)
Changing the current directory of the script process is trivial. I think the question is actually how to change the current directory of the command window from which a python script is invoked, which is very difficult. A Bat script in Windows or a Bash script in a Bash shell can do this with an ordinary cd command because the shell itself is the interpreter. In both Windows and Linux Python is a program and no program can directly change its parent's environment. However the combination of a simple shell script with a Python script doing most of the hard stuff can achieve the desired result. For example, to make an extended cd command with traversal history for backward/forward/select revisit, I wrote a relatively complex Python script invoked by a simple bat script. The traversal list is stored in a file, with the target directory on the first line. When the python script returns, the bat script reads the first line of the file and makes it the argument to cd. The complete bat script (minus comments for brevity) is:
if _%1 == _. goto cdDone
if _%1 == _? goto help
if /i _%1 NEQ _-H goto doCd
:help
echo d.bat and dSup.py 2016.03.05. Extended chdir.
echo -C = clear traversal list.
echo -B or nothing = backward (to previous dir).
echo -F or - = forward (to next dir).
echo -R = remove current from list and return to previous.
echo -S = select from list.
echo -H, -h, ? = help.
echo . = make window title current directory.
echo Anything else = target directory.
goto done
:doCd
%~dp0dSup.py %1
for /F %%d in ( %~dp0dSupList ) do (
cd %%d
if errorlevel 1 ( %~dp0dSup.py -R )
goto cdDone
)
:cdDone
title %CD%
:done
The python script, dSup.py is:
import sys, os, msvcrt
def indexNoCase ( slist, s ) :
for idx in range( len( slist )) :
if slist[idx].upper() == s.upper() :
return idx
raise ValueError
# .........main process ...................
if len( sys.argv ) < 2 :
cmd = 1 # No argument defaults to -B, the most common operation
elif sys.argv[1][0] == '-':
if len(sys.argv[1]) == 1 :
cmd = 2 # '-' alone defaults to -F, second most common operation.
else :
cmd = 'CBFRS'.find( sys.argv[1][1:2].upper())
else :
cmd = -1
dir = os.path.abspath( sys.argv[1] ) + '\n'
# cmd is -1 = path, 0 = C, 1 = B, 2 = F, 3 = R, 4 = S
fo = open( os.path.dirname( sys.argv[0] ) + '\\dSupList', mode = 'a+t' )
fo.seek( 0 )
dlist = fo.readlines( -1 )
if len( dlist ) == 0 :
dlist.append( os.getcwd() + '\n' ) # Prime new directory list with current.
if cmd == 1 : # B: move backward, i.e. to previous
target = dlist.pop(0)
dlist.append( target )
elif cmd == 2 : # F: move forward, i.e. to next
target = dlist.pop( len( dlist ) - 1 )
dlist.insert( 0, target )
elif cmd == 3 : # R: remove current from list. This forces cd to previous, a
# desireable side-effect
dlist.pop( 0 )
elif cmd == 4 : # S: select from list
# The current directory (dlist[0]) is included essentially as ESC.
for idx in range( len( dlist )) :
print( '(' + str( idx ) + ')', dlist[ idx ][:-1])
while True :
inp = msvcrt.getche()
if inp.isdigit() :
inp = int( inp )
if inp < len( dlist ) :
print( '' ) # Print the newline we didn't get from getche.
break
print( ' is out of range' )
# Select 0 means the current directory and the list is not changed. Otherwise
# the selected directory is moved to the top of the list. This can be done by
# either rotating the whole list until the selection is at the head or pop it
# and insert it to 0. It isn't obvious which would be better for the user but
# since pop-insert is simpler, it is used.
if inp > 0 :
dlist.insert( 0, dlist.pop( inp ))
elif cmd == -1 : # -1: dir is the requested new directory.
# If it is already in the list then remove it before inserting it at the head.
# This takes care of both the common case of it having been recently visited
# and the less common case of user mistakenly requesting current, in which
# case it is already at the head. Deleting and putting it back is a trivial
# inefficiency.
try:
dlist.pop( indexNoCase( dlist, dir ))
except ValueError :
pass
dlist = dlist[:9] # Control list length by removing older dirs (should be
# no more than one).
dlist.insert( 0, dir )
fo.truncate( 0 )
if cmd != 0 : # C: clear the list
fo.writelines( dlist )
fo.close()
exit(0)
os.chdir() is the right way.
Here's an example of a context manager to change the working directory. It is simpler than an ActiveState version referred to elsewhere, but this gets the job done.
cdimport os
class cd:
"""Context manager for changing the current working directory"""
def __init__(self, newPath):
self.newPath = os.path.expanduser(newPath)
def __enter__(self):
self.savedPath = os.getcwd()
os.chdir(self.newPath)
def __exit__(self, etype, value, traceback):
os.chdir(self.savedPath)
Or try the more concise equivalent(below), using ContextManager.
import subprocess # just to call an arbitrary command e.g. 'ls'
# enter the directory like this:
with cd("~/Library"):
# we are in ~/Library
subprocess.call("ls")
# outside the context manager we are back wherever we started.
cd() is easy to write using a generator and a decorator.
from contextlib import contextmanager
import os
@contextmanager
def cd(newdir):
prevdir = os.getcwd()
os.chdir(os.path.expanduser(newdir))
try:
yield
finally:
os.chdir(prevdir)
Then, the directory is reverted even after an exception is thrown:
os.chdir('/home')
with cd('/tmp'):
# ...
raise Exception("There's no place like /home.")
# Directory is now back to '/home'.
I would use os.chdir like this:
os.chdir("/path/to/change/to")
By the way, if you need to figure out your current path, use os.getcwd().
More here
Changing the current directory of the script process is trivial. I think the question is actually how to change the current directory of the command window from which a python script is invoked, which is very difficult. A Bat script in Windows or a Bash script in a Bash shell can do this with an ordinary cd command because the shell itself is the interpreter. In both Windows and Linux Python is a program and no program can directly change its parent's environment. However the combination of a simple shell script with a Python script doing most of the hard stuff can achieve the desired result. For example, to make an extended cd command with traversal history for backward/forward/select revisit, I wrote a relatively complex Python script invoked by a simple bat script. The traversal list is stored in a file, with the target directory on the first line. When the python script returns, the bat script reads the first line of the file and makes it the argument to cd. The complete bat script (minus comments for brevity) is:
if _%1 == _. goto cdDone
if _%1 == _? goto help
if /i _%1 NEQ _-H goto doCd
:help
echo d.bat and dSup.py 2016.03.05. Extended chdir.
echo -C = clear traversal list.
echo -B or nothing = backward (to previous dir).
echo -F or - = forward (to next dir).
echo -R = remove current from list and return to previous.
echo -S = select from list.
echo -H, -h, ? = help.
echo . = make window title current directory.
echo Anything else = target directory.
goto done
:doCd
%~dp0dSup.py %1
for /F %%d in ( %~dp0dSupList ) do (
cd %%d
if errorlevel 1 ( %~dp0dSup.py -R )
goto cdDone
)
:cdDone
title %CD%
:done
The python script, dSup.py is:
import sys, os, msvcrt
def indexNoCase ( slist, s ) :
for idx in range( len( slist )) :
if slist[idx].upper() == s.upper() :
return idx
raise ValueError
# .........main process ...................
if len( sys.argv ) < 2 :
cmd = 1 # No argument defaults to -B, the most common operation
elif sys.argv[1][0] == '-':
if len(sys.argv[1]) == 1 :
cmd = 2 # '-' alone defaults to -F, second most common operation.
else :
cmd = 'CBFRS'.find( sys.argv[1][1:2].upper())
else :
cmd = -1
dir = os.path.abspath( sys.argv[1] ) + '\n'
# cmd is -1 = path, 0 = C, 1 = B, 2 = F, 3 = R, 4 = S
fo = open( os.path.dirname( sys.argv[0] ) + '\\dSupList', mode = 'a+t' )
fo.seek( 0 )
dlist = fo.readlines( -1 )
if len( dlist ) == 0 :
dlist.append( os.getcwd() + '\n' ) # Prime new directory list with current.
if cmd == 1 : # B: move backward, i.e. to previous
target = dlist.pop(0)
dlist.append( target )
elif cmd == 2 : # F: move forward, i.e. to next
target = dlist.pop( len( dlist ) - 1 )
dlist.insert( 0, target )
elif cmd == 3 : # R: remove current from list. This forces cd to previous, a
# desireable side-effect
dlist.pop( 0 )
elif cmd == 4 : # S: select from list
# The current directory (dlist[0]) is included essentially as ESC.
for idx in range( len( dlist )) :
print( '(' + str( idx ) + ')', dlist[ idx ][:-1])
while True :
inp = msvcrt.getche()
if inp.isdigit() :
inp = int( inp )
if inp < len( dlist ) :
print( '' ) # Print the newline we didn't get from getche.
break
print( ' is out of range' )
# Select 0 means the current directory and the list is not changed. Otherwise
# the selected directory is moved to the top of the list. This can be done by
# either rotating the whole list until the selection is at the head or pop it
# and insert it to 0. It isn't obvious which would be better for the user but
# since pop-insert is simpler, it is used.
if inp > 0 :
dlist.insert( 0, dlist.pop( inp ))
elif cmd == -1 : # -1: dir is the requested new directory.
# If it is already in the list then remove it before inserting it at the head.
# This takes care of both the common case of it having been recently visited
# and the less common case of user mistakenly requesting current, in which
# case it is already at the head. Deleting and putting it back is a trivial
# inefficiency.
try:
dlist.pop( indexNoCase( dlist, dir ))
except ValueError :
pass
dlist = dlist[:9] # Control list length by removing older dirs (should be
# no more than one).
dlist.insert( 0, dir )
fo.truncate( 0 )
if cmd != 0 : # C: clear the list
fo.writelines( dlist )
fo.close()
exit(0)
If you use spyder and love GUI, you can simply click on the folder button on the upper right corner of your screen and navigate through folders/directories you want as current directory. After doing so you can go to the file explorer tab of the window in spyder IDE and you can see all the files/folders present there. to check your current working directory go to the console of spyder IDE and simply type
pwd
it will print the same path as you have selected before.
I would use os.chdir like this:
os.chdir("/path/to/change/to")
By the way, if you need to figure out your current path, use os.getcwd().
More here
If you use spyder and love GUI, you can simply click on the folder button on the upper right corner of your screen and navigate through folders/directories you want as current directory. After doing so you can go to the file explorer tab of the window in spyder IDE and you can see all the files/folders present there. to check your current working directory go to the console of spyder IDE and simply type
pwd
it will print the same path as you have selected before.
If you're using a relatively new version of Python, you can also use a context manager, such as this one:
from __future__ import with_statement
from grizzled.os import working_directory
with working_directory(path_to_directory):
# code in here occurs within the directory
# code here is in the original directory
UPDATE
If you prefer to roll your own:
import os
from contextlib import contextmanager
@contextmanager
def working_directory(directory):
owd = os.getcwd()
try:
os.chdir(directory)
yield directory
finally:
os.chdir(owd)
os.chdir() is the right way.
As already pointed out by others, all the solutions above only change the working directory of the current process. This is lost when you exit back to the Unix shell. If desperate you can change the parent shell directory on Unix with this horrible hack:
def quote_against_shell_expansion(s):
import pipes
return pipes.quote(s)
def put_text_back_into_terminal_input_buffer(text):
# use of this means that it only works in an interactive session
# (and if the user types while it runs they could insert characters between the characters in 'text'!)
import fcntl, termios
for c in text:
fcntl.ioctl(1, termios.TIOCSTI, c)
def change_parent_process_directory(dest):
# the horror
put_text_back_into_terminal_input_buffer("cd "+quote_against_shell_expansion(dest)+"\n")
I would use os.chdir like this:
os.chdir("/path/to/change/to")
By the way, if you need to figure out your current path, use os.getcwd().
More here
If You would like to perform something like "cd.." option, just type:
os.chdir("..")
it is the same as in Windows cmd: cd.. Of course import os is neccessary (e.g type it as 1st line of your code)
The Path objects in path library offer both a context manager and a chdir method for this purpose:
from path import Path
with Path("somewhere"):
...
Path("somewhere").chdir()
Here's an example of a context manager to change the working directory. It is simpler than an ActiveState version referred to elsewhere, but this gets the job done.
cdimport os
class cd:
"""Context manager for changing the current working directory"""
def __init__(self, newPath):
self.newPath = os.path.expanduser(newPath)
def __enter__(self):
self.savedPath = os.getcwd()
os.chdir(self.newPath)
def __exit__(self, etype, value, traceback):
os.chdir(self.savedPath)
Or try the more concise equivalent(below), using ContextManager.
import subprocess # just to call an arbitrary command e.g. 'ls'
# enter the directory like this:
with cd("~/Library"):
# we are in ~/Library
subprocess.call("ls")
# outside the context manager we are back wherever we started.
os.chdir() is the Pythonic version of cd.
os.chdir() is the right way.
As already pointed out by others, all the solutions above only change the working directory of the current process. This is lost when you exit back to the Unix shell. If desperate you can change the parent shell directory on Unix with this horrible hack:
def quote_against_shell_expansion(s):
import pipes
return pipes.quote(s)
def put_text_back_into_terminal_input_buffer(text):
# use of this means that it only works in an interactive session
# (and if the user types while it runs they could insert characters between the characters in 'text'!)
import fcntl, termios
for c in text:
fcntl.ioctl(1, termios.TIOCSTI, c)
def change_parent_process_directory(dest):
# the horror
put_text_back_into_terminal_input_buffer("cd "+quote_against_shell_expansion(dest)+"\n")
If You would like to perform something like "cd.." option, just type:
os.chdir("..")
it is the same as in Windows cmd: cd.. Of course import os is neccessary (e.g type it as 1st line of your code)
os.chdir() is the Pythonic version of cd.
cd() is easy to write using a generator and a decorator.
from contextlib import contextmanager
import os
@contextmanager
def cd(newdir):
prevdir = os.getcwd()
os.chdir(os.path.expanduser(newdir))
try:
yield
finally:
os.chdir(prevdir)
Then, the directory is reverted even after an exception is thrown:
os.chdir('/home')
with cd('/tmp'):
# ...
raise Exception("There's no place like /home.")
# Directory is now back to '/home'.
import os
abs_path = 'C://a/b/c'
rel_path = './folder'
os.chdir(abs_path)
os.chdir(rel_path)
You can use both with os.chdir(abs_path) or os.chdir(rel_path), there's no need to call os.getcwd() to use a relative path.
Further into direction pointed out by Brian and based on sh (1.0.8+)
from sh import cd, ls
cd('/tmp')
print ls()
I would use os.chdir like this:
os.chdir("/path/to/change/to")
By the way, if you need to figure out your current path, use os.getcwd().
More here
os.chdir() is the Pythonic version of cd.
Further into direction pointed out by Brian and based on sh (1.0.8+)
from sh import cd, ls
cd('/tmp')
print ls()
If you're using a relatively new version of Python, you can also use a context manager, such as this one:
from __future__ import with_statement
from grizzled.os import working_directory
with working_directory(path_to_directory):
# code in here occurs within the directory
# code here is in the original directory
UPDATE
If you prefer to roll your own:
import os
from contextlib import contextmanager
@contextmanager
def working_directory(directory):
owd = os.getcwd()
try:
os.chdir(directory)
yield directory
finally:
os.chdir(owd)
Source: Stackoverflow.com